Lock



`luly 3, 1934. w C, sHlNN 1,964,963

LOCK

Filed Jan. 16, 1933 Patented July 3, 1934 UNITED STATES PATENT OFFICE LOCK of Illinois Application January 16,

7 Claims.

The present invention relates generally to locks. More particularly, the invention relates to that type of lock which is designed to be pickproof and comprises (l) a cylindrical casing having a bore extending longitudinally therethrough; (2) a plug which is mounted rotatably in the bore and has a longitudinal slot for a key; and (3) a series or group of key-operable plate tumblers which are mounted in the plug to slide transversely of the latter and also to rock laterally to a slight degree, serve upon removal of the key from the lock, to lock the plug against rotation relatively to the casing and have at the ends thereof laterally extending hooks adapted, when an attemptis made to pick the lock by manipulating the tumblers with a pin or wire and turning the plug as far as permitted by the tumblers so as to hold the tumblers frictionally in place, to be shifted into engagement with parts of the plug in response to turning of the plug and thus to hold the tumblers so that the tumblers cannot be manipulated transversely of the plug for lock-opening purposes.

One object of the invention is to provide a lock of this type which is more eflicient in operation than previously designed locks of the same general character by reason of the fact that it embodies a spring whereby the tumblers are automatically rocked laterally for hook-engaging purposes immediately upon removal of the key from the plug, and are held yeldingly in their hooked position so as positively to preclude picking of the lock.

Another object of the invention is to provide a lock of the last mentioned character in which the spring for rocking the tumblers laterally for hook-engaging purposes is arranged so that it rocks some of the tumblers in one direction and others in the opposite direction.

Another object of the invention is to provide a pick-proof lock of the type and character under consideration in which the spring for rocking the tumblers laterally for hook-engaging purposes is constructed and arranged so that it operates additionally to shift the tumblers transversely of the plug into locked relation with the casing when the key is removed from the slot.

A further object of the invention is to provide a lock of the aforementioned type in which the group of tumblers which are rocked laterally in one direction by the spring are separated from the tumblers which are rocked in the opposite direction by means of a plate which is secured against transverse movement relatively to the plug and serves to guide' the key so that it rocks 1933, Serial No. 651,947

(Cl. Y0-46) the tumblers out of hook-engaging position when it is inserted into the key slot for lock-opening purposes.

A still further object of the invention is to provide a lock which is generally of new and improved construction, may be manufactured at a low and reasonable cost and is an improvement upon the locks exhibited in Letters Patent of the United States Nos. 1,406,573 and 1,644,092 dated respectively February 14, 1922 and October 4, 1927.

Other objects of the invention and the various advantages and characteristics of the present lock construction will be apparent from a consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly dened by claims at the conclusion hereof.

In the'drawing which accompanies and forms a part of this speciiication or disclosure and in which like numerals of reference denote corresponding parts throughout the several views:

Figure l is a view, partly in plan and partly in section, of a lock embodying the invention, the key for the lock being shown in its operative position;

Figure 2 is a similar view, the key, however, being shown removed from the plug;

Figure 3 is a vertical transverse section illustrating the manner in which the tumblers hold the plug against rotation relatively to the casing when the lock is in its locked position;

Figure 4. is a vertical transverse section on the line 4 4 of Figure 3;

Figure 5 is a vertical transverse section taken on the line 5 5 of Figure 3, exhibiting the manner in which the tumblers are rocked laterally into hook-engaging position by the spring when the key is removed from the plug;

Figure 6 is a vertical transverse section on the line 6 6 of Figure 3 and discloses the cross sectional construction of the plug and casing; and

Figure 7 is a perspective of the tumblers and spring.

The lock which forms the subject matter of the invention is adapted for universal application and comprises a casing8 and a plug 9. The casing is cylindrical and embodies a longitudinal bore`10. This bore extends completely through the casing and is of uniform diameter throughout withthe exception of the front end which is of slightly larger diameter and results in the formation of an annular shoulder 11 at the front end of the casing. The casing is preferably formed of any suitable hardened metal and is adapted to be xedly secured with respect to the device to which the lock is applied. The plug 9 is cylindrical and extends through, and fits rotatably in, the bore 10 in the casing, and is formed of any suitable metal. It embodies at the front end thereof an enlarged head 12. This head, as shown in the drawing, ts within the enlarged front end portion of the bore 9 and abuts against the annular shoulder 11 so as to hold the plug against rearward displacement with respect to the casing. A spring pressed holding element 13 is carried by the rear end of the plug and abuts against the rear end of the casing so as to hold the plug against frontward displacement with respect to the casing. A stud 14 is formed integrally with and projects rearwardly from the rear end of the plug and is adapted to be connected to operate the bolt or other locking instrumentality controlled by the lock. The plug, in addition to the stud and head embodies a longitudinal slot 15 for a key 16. The latter is designed to control the operation of the lock and embodies longitudinal grooves 16i1 in the operating end thereof. The key slot l5 extends through the central portion of the plug and conforms in cross sectional shape or design to the operating end of the key 16. It is intersected in the central portion thereof by a pocket 17. The latter extends transversely through the plug and is substantially rectangular.

Rotation of the plug relatively to the casing is controlled by a series or group of plate turnblers 18. These tumblers are mounted in a metallic frame 19 which is disposed in the pocket 17 and supports or confines the tumblers so that they are free to slide transversely of the plug. The ends of the plate tumblers are adapted to t within a pair of diametrically opposite grooves 20 and operate when disposed in these grooves, to lock the plug against rotation. The grooves 20, as shown in the drawing, open onto the bore 10 and extend longitudinally of the casing and from the shoulder 11 to the rear end of the casing. Slots 21 are formed in the central portions of the tumblers and permit the operating end of the key to pass through the tumblers. rThese slots are shaped so that they cooperate with the operating end of the key to shift the tumblers into a position wherein the ends thereof are fiush with the periphery of the plug when the key is inserted into the lock. In this position of the tumblers, the plug is free so that it may be rotated relatively to the casing for bolt-throwing or other purposes. When the key is removed, the tumblers are shifted transversely of the plug and into interlocked relation with the grooves 20 by means of a spring 22 in order to lock the plug against rotation.

The frame 19 which supports the tumblers Within the pocket 17 may be considered a part of the plug 9 and consists of a front wall 23, a side Wall 24 and a rear Wall 25. The front and rear walls 23 and 25 fit respectively against the surfaces of the plug which define the front and rear ends of the pocket 17 and hold the frame 19 frictionally in place. They embody slots 26 which are longitudinally aligned with, and are shaped similarly to, the key slot 15 and receive and guide the operating end of the key when the key is inserted into place to unlock the lock. The side wall 24 ts against the face of the plug which forms one of the sides of the pocket 17 and extends between, and is formed integrally with, the front and rear Walls 23v and 25 at one side of the frame.

At the other side of the frame, the side margins of the front and rear walls 23 and 25 are cut away so as to form laterally extending studs 27. These studs are positioned centrally with respect to the frame and serve as hereinafter described, to support the spring 22.

The spring 22 for urging the tumblers transversely of the plug into locked relation with the casing is formed of a single piece of wire and consists of a central part 22qu and a pair of end parts or arms 22b and 22C. These arms are connected to the central part 22a by a pair of coils 22d. The latter, as shown in Figures 3 and 7 of the drawing, are mounted on the studs 27 respectively and urge outwardly in opposite directions the arms 22b and 22c for tumbler-shifting purposes. The arms of the spring urge outwardly the tumblers for plug-locking purposes, through the medium of lugs 28 which are formed integrally with the ends of the plate tumblers and project laterally in the direction of the spring. The arm 22b is shaped so that it shifts outwardly in one direction the tumblers at the rear of the frame and the arm 22c is shaped and arranged so that it shifts outwardly in the opposite directions the tumblers at the front of the frame. By arranging the arms of the spring in this manner, some of the tumblers are projected or shifted into one of the grooves 20 and the other tumblers are shifted into the other groove by the spring when the key is removed from the lock. The side of the pocket 17 opposite the side wall 24 of the frame serves to hold the coils 22d of the spring on the studs 27 and forms a sliding surface or bearing for the lugs 28.

In order to render the lock pick-proof, the tumblers 18 are constructed so that they are free to rock laterally to a limited extent relatively to the plug, and embody at the ends thereof hooks 29. The latter are formed integrally with and project laterally from the ends of the tumblers in the direction of the side wall 24 of the frame 19 and are adapted when the lock is in its locked position and in response to rocking of the tum blers, to engage the side edges of the side wall 24, as shown in Figure 5, and to hold the tumblers against transverse movement with respect tothe plug. When the tumblers 18 are in their locked position and are rocked laterally so that the hooks 29 engage the side edges of the side wall 24 of the frame, it is impossible to pick the lock because the tumblers cannot berretracted into the pocket of the plug by means of a wire or pin inserted through the key slot. The key for the lock, when inserted into the key slot, is adapted to rock the tumblers out of hooked relation with the side wall 24 and to withdraw them into the pocket as previously pointed out, so that the plug may be rotated relatively to the casing and shifted or turned to its unlocked position. The hooks 29 are adapted when the tumblers are retracted by the key, to slide against the inner face of the side wall 24.

For the purpose of rocking the tumblers automatically into hooked relation with the side wall of the frame upon removal of the key from the key slot 15, the distal end of the arm 22b of the spring 22 is doubled back and bent outwardly to form a loop-like extension 22e and the distal end of the arm 22c is doubled back and bent outwardly to form a loop-like extension 22f. These looplike extensions, as shown particularly in Figures' 2 and 5 of the drawing, bear against the face of the pocket opposite the side wall 24 of the frame and urge the tumblers laterally. When the tumblers are projected or shifted outwardly into interlocked relation with the grooves 20 in the casing, the extensions rock the tumblers laterally into hooked relation with the side wall of the frame. The extension 22e rocks the tumblers at the rear of the frame laterally in one direction and into hooked relation with one side edge of the side Wall of the frame, and the extension 22f rocks the tumblers at the front of the frame laterally in the opposite direction and into hooked relation with the other side edge of the frame side wall. As a result of rocking the rear and front tumblers laterally in opposite directions, picking of the lock is effectively prevented, inasmuch as some of the tumblers are always in hooked relation with the side Wall of the frame regardless of whether the plug is turned in one direction or the other for tumbler-righting purposes.

In order properly to guide the key, a plate 30 is provided. This plate separates the tumblers at the rear of the frame from those at the front of the frame and has a central key slot 3l which is aligned with, and is shaped similarly to, the key slots 26 in the front and rear walls of the frame. The plate is held against transverse displacement with respect to the plug by means of a pair of laterally extending ears 32. rIhe latter engage respectively the side edges of the side wall of the frame and serve to hold in place the guide plate.

When the lock is to be opened, the working end of the key 16 is inserted into the key slot 15 and the key is shifted forwardly so as to force the working end through the slots in the guide plate and the front and rear walls of the frame and also through the slots 21. This movement of the key serves to right the tumblers and to with-draw them into the pocket 17 so that the ends thereof are flush with the periphery of the plug and the plug is free to turn or rotate in the casing. When it is desired to lock the lock, the key 16 is removed. Upon removal of the key from the key slot 15, the arms 22b and 22c of the spring 22 force the tumblers outwardly into interlocked relation with the grooves 20. Upon outward shift of the tumblers by the arms of the spring, the loop-like extensions 22e and 22b of the spring rock the tumblers into hooked relation with the side wall of the frame. In their hooked position, the tumblers, as previously pointed out, are held against transverse movement relatively to the plug and the lock cannot be picked,

The herein described lock consists of but a small number of parts and may be manufactured at a low and reasonable cost. It is exceedingly efficient in operation in that it is completely pick-proof.

The invention is not to be understood as restricted to the details set forth, since these may be modified within the scope of the appended claims, Without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a lock, the combination of a casing, a plug mounted rotatably in the casing and provided with a key slot, a set of key-operable plate tumblers mounted loosely in the plug to move sidewise to a limited extent and also to slide transversely of the plug into and out of locked relation with the casing, devices operative in response to sidewise movement of the tumblers to hold said tumblers against transverse movement when they are in their locked position in order to prevent picking of the lock, and means for automatically moving the tumblers sidewise upon shift thereof into said locked position.

2. In a lock, the combination of a casing, a plug mounted rotatably in the casing and provided with a key slot, a set of key-operable plate tumblers mounted loosely in the plug to move sidewise to a limited extent and also to slide transversely of the plug into and out of locked relation with the casing, devices operative in response to sidewise movement of the tumblers to hold said tumblers against transverse movement when they are in their locked position in order to prevent picking of the lock, and spring means for moving the tumblers laterally upon shift thereof into said locked position.

3. In a lock, the combination of a casing, a plug mounted rotatably in the casing and provided with a key slot, a set of key-operable plate tumblers mounted in the plug to slide transversely of the latter into and out of locked relation with the casing and also to rock laterally to a limited extent, laterally extending hooks on both ends of the tumblers operative in response to rocking of the tumblers to engage parts of the plug and hold the tumblers against transverse movement when they are in their locked position in order to prevent picking of the lock, and spring means for rocking some of the tumblers in one direction and others in the opposite direction upon shift of the tumblers into said locked position.

Ll. In a lock of the character described, the combination of a casing having a longitudinal bore and a groove along the bore, a plug mounted rotatably along the bore and provided with a slot for the key for the lock, a set of plate tumblers .Y

mounted in the plug so that they are free to rock laterally to a limited extent and also to slide transversely of the plug in order to bring the ends thereof into the groove and thus lock the plug against rotation relatively to the casing, hooks on the ends of the tumblers operative in response to rocking of the tumblers to engage parts of the tumblers and hold the plug against transverse movement when they are in their locked position in order to prevent picking of the lock, spring means for sliding the tumblers outwardly into their locked position upon removal of the key from the slot, and means for automatically rocking the tumblers into their hooked position upon outward shift thereof into their locked position,

by the spring means.

5. In a lock of the character described, the combination of a casing having a longitudinal bore and a groove along the bore, a plug mounted rotatably along the bore and provided with a slot for the key for the lock, a set of plate tumblers mounted in the plug so that they are free to rock laterally to a limited extent and also to slide transversely of the plug in order to bring the ends thereof into the groove and thus lock the plug against rotation relatively to the casing, hooks on the ends of the tumblers operative in response to rocking of the tumblers to engage parts of the tumblers and hold the plug against transverse movement when they are in their locked position in order to prevent picking of the lock, and a spring arranged and constructed to shift the tumblers transversely into their locked position upon removal of the key and at the same time, to rock them into their hooked position.

6. In a lock of the character described, the combination of a casing having a longitudinal bore and a groove along the bore, a plug mounted rotatably along the bore and provided with a slot for the key for the lock, a set of plate tumblers mountedinthe.plugfsofthattheyre free t0 .rock

laterally to a limited extent andalso to slide transsome laterally in one direction and others lateral- Aly in theopposite directionduring shift of the tnmblers,V into i saidv .locked position.

A7. In a 1ock, the combination lof a casing having a bore therethrough and a groove at one side, and longitudinal of said bore, a plug mounted rotatablyin, and removable from the bore and provided With a longitudinal slot for the key for the the lock and a transversely extending pocket in ,tersecting said key slot, key-operable plate tumblers mounted in the pocket so that they are free to slide transversely of the plug into and out of interlocking relation with the groove in the casing, and a separately formed guide plate for the key extending transversely across the central portion of the pocket and serving to separate the tumblers into groups, said plate being provided at the ends thereof with laterally projecting lugs whereby it is locked against transverse movement relatively to the plug when the latter is mounted in place in the bore of the casing,

WILLIAM C. SHINN. 

